1. Field of the Invention
The present invention relates to radiation imaging technology, and more particularly to a method of manufacturing a structured, auto-collimating scintillator.
2. Brief Description of the Prior Art
In U.S. Pat. No. 4,069,355 to Lubowski et al, there is described a process for forming a patterned substrate using wide-angled vapor deposition techniques so as to deposit a phosphor on the raised portion of the substrate, including the steps of vapor deposition of a phosphor, such as cesium iodide.
In U.S. Pat. No. 4,842,894 to Ligtenberg et al, there is disclosed a process for vapor deposition of a luminescent layer on a screen substrate wherein the vapor deposition crucible is rotated about an axis perpendicular to the screen.
In conventional thin film deposition techniques involves the changing of the surface properties of substrate materials to impart advantageous characteristics, e.g., a corrosion-resistant coating, etc., successful surface modification depends on the deposition of a continuous, defect-free coating layer. Conversely, an effective auto-collimating screen layer must be replete with uniform structural discontinuities.
In this connection, for example, reference is made to U.S. Pat. No. 5,171,996 to Perez-Mendez wherein there is described a method for fabricating a particle detector of a sequence of columns of regular, controllable geometry and diameter perpendicular to the interface of luminescent material with adjacent materials wherein the columns are separated by gaps which may be evacuated or filled with air with a light-absorbing material or with a light-producing or light-reflective substance. While the processes of the prior art have achieved certain levels of performance, there is a desire to optimize a performance of a structured, auto-collimating scintillator to achieve high ionizing radiation to luminescent conversion efficiency as well as high spacial resolution.